Institute of Technology of Agricultural Products, Hellenic Agricultural Organization DEMETER, 1 Sof. Venizelou Str, Lykovrisi, Athens, 14123, Greece.
Institute of Technology of Agricultural Products, Hellenic Agricultural Organization DEMETER, 1 Sof. Venizelou Str, Lykovrisi, Athens, 14123, Greece.
Food Microbiol. 2018 Sep;74:21-33. doi: 10.1016/j.fm.2018.02.005. Epub 2018 Feb 10.
The aim of the study was to investigate the performance of Lactobacillus plantarum T571 with probiotic potential as a co-starter culture in Feta cheese production and in its long-term storage. For this reason, Feta cheese was manufactured without (control) or with the probiotic T571 strain (probiotic) and then monitored during storage at 4 and 12 °C, respectively. The products were also inoculated with Listeria monocytogenes (3-strain cocktail). The results showed that lactic acid bacteria exceeded 6 log CFU/g during storage in all trials. The probiotic samples displayed higher acidity (≈1.5% lactic acid) and lower pH (≈4.2). Coliforms and L. monocytogenes, were inactivated in shorter time in probiotic samples, in comparison with the control ones. Pulsed field gel electrophoresis verified the presence of the probiotic strain in the cheese, until the end of storage at both temperatures, whilst the survival and distribution of the pathogenic strains depended on the trial. The sensory evaluation showed that the probiotic cheeses had desirable sensory characteristics similar to the control ones, with scores of ca. 8 on a 10 cm-scale. Finally, Fourier transform infrared spectroscopy was applied for the first time during Feta cheese storage with promising results for the rapid estimation of the microbiological counts and sensory status of cheese. Results showed that Lb. plantarum T571 highlighted desirable and robust technological properties and may be used in cheese making as an adjunct culture.
本研究旨在探讨具有益生菌潜力的植物乳杆菌 T571 作为共发酵剂在羊乳干酪生产及其长期储存中的性能。为此，分别使用（对照）或不使用益生菌 T571 菌株（益生菌）制造羊乳干酪，并在 4 和 12°C 下储存时进行监测。产品还接种了单核细胞增生李斯特菌（3 株混合）。结果表明，在所有试验中，乳酸菌在储存过程中均超过 6 log CFU/g。益生菌样品的酸度（≈1.5%乳酸）更高，pH 值（≈4.2）更低。与对照样品相比，益生菌样品中大肠菌群和单核细胞增生李斯特菌的失活时间更短。脉冲场凝胶电泳证实了益生菌菌株在奶酪中的存在，直至在两种温度下储存结束，而病原菌的存活和分布取决于试验。感官评价表明，益生菌干酪具有理想的感官特性，与对照样品相似，在 10cm 尺度上的评分为约 8。最后，首次将傅里叶变换红外光谱应用于羊乳干酪储存中，为快速估计奶酪的微生物计数和感官状态提供了有希望的结果。结果表明，Lb. plantarum T571 具有良好的技术性能，可能作为辅助发酵剂用于奶酪制作。
